Early Physical Therapy for Low Back Pain Shows Modest Benefits

Study found patients with acute low back pain may benefit from an early intervention of physical therapy.

Low back pain (LBP) is common among many Americans, and even as health care spending increases, so does the prevalence of poor outcomes associated with it.1 Most patients with acute, early-onset LBP (<16 days duration) typically visit their primary care provider,2 who may delay referral to a physical therapist out of hope they will have a spontaneous recovery,3 something typical of acute LBP patients.4Early physical therapy (PT) may have a beneficial effect on the recovery process, according to a study published in JAMA. Whether it provides a clinically significant difference in the long run is debatable, though.

No Significant Long-Term Difference
The longitudinal study looked at 220 LBP patients to see if applying an early 4-session regimen of PT made a discernible difference in outcomes after 4 weeks, 3 months, or 1 year. Using the Oswestry Disability Index (ODI),5 the researchers found early physical therapy provided a “statistically significant” effect, with ODI scores noticeably lower (-3.2 [95% CI,−5.9 to −0.47], P=.02) at 3 months. “But the magnitude of the difference was modest and did not achieve the minimum difference considered clinically important at the individual patient level,” the authors wrote.

A clinically significant difference would have been 6 points on the ODI, which has a 100-point scale measuring physical function.6 Patients participating in early PT showed their best marks after the first 4 weeks, reaching a peak ODI difference from the usual care cohort of −3.5 [95%CI, −6.8 to −0.08], P=.045]. However, after a year, the difference decreased to negligible: −2.0 [95%CI, −5.0 to 1.0], P=.19).

Early intervention patients also showed better improvements in their fear avoidance to work, especially at 3 months. However, other secondary outcomes were not remarkably different. Early PT also showed patients rated their overall health much lower than patients on usual care.

Target LBP Subgroup for Early Physical Therapy?
A subgroup of patients with low back pain, who may be responsive to early physical therapy may demonstrate:

At least moderate disability (ODI score ≥20)

An acute onset with <16 days of duration

No symptoms distal to the knee(s)

No clinical findings suggesting nerve root compression

“We selected this subgroup because it is linked to a specific physical therapy protocol of spinal manipulation and exercise, which are evidence-based low back pain treatments.3 The majority of exclusions resulted from the acuity criterion (<16 days duration). This criterion maximized likelihood of success with this physical therapy protocol in prior research,7 ” the authors wrote.

There could be a specific subgroup of patients with LBP that benefit to early PT, something that seems “possible and logical," but still very hard to prove, said Julie M. Fritz, PhD, PT, Professor of Physical Therapy at the University of Utah in Salt Lake City, Utah.

“We know that most patients do well rapidly, but some don’t. While the ability to figure out how to target treatment to those unlikely to recover is a very important research goal, it has been difficult to determine,” stated Dr. Fritz. Furthermore, she indicated, “PT can provide some assistance with a slightly more rapid improvement on average. For patients with acute LBP who want or need a little assistance in getting back to regular activities, physical therapy can help.”

Important Limitations
A notable limitation is how the researchers tested patients with a 4-session physical therapy routine. While 4 sessions may be more “practical for routine clinical use,” (national average is 7 or more sessions for LBP2) it still begs the question, “If there were more sessions, would there have been greater outcome success?”

“I don’t think so,” said Dr. Fritz. “The small effect of PT was not because patients weren’t getting better—they did get better rapidly. Since most patients do well without physical therapy, we need to be very efficient in providing PT if it is to be shown cost-effective. In other words, if benefits are small, it is important to keep costs low.

“The potential benefits of early physical therapy should be considered in light of the time and effort required to participate in physical therapy,” the study authors wrote. While other early intervention options have been shown to prolong disability and lead to more invasive procedures, early physical therapy by contrast seems to show a positive effect, however, modest that may be.

This study was funded through a grant from the Agency for Healthcare Research and Quality, with support from the University of Utah Study Design and Biostatistics Center and grants from the National Center for Research Resources and the National Center for Advancing Translational Sciences of the National Institutes of Health. Lead author the study, Julie M. Fritz, PhD, PT, reported receiving personal fees from Focus On Therapeutic Outcomes. No other disclosures were reported by the study authors.